This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Explore the use of chitosan as the barrier modulating agent for the delivery of therapeutic agents specifically, BDNF and levodopa. Specific Aim 1: To investigate the effect of chitosan on the permeation of markers of different molecular weight across olfactory mucosa. Specific Aim 2: To study the effect of chitosan on the permeation of BDNF and levodopa across the olfactory mucosa. Specific Aim 3: To study the effect of chitosan on nose to brain bioavailability of BDNF and Levodopa in rat model. Specific Aim 4: To prepare drug-polymer co-micelle systems and to investigate their permeability across the olfactory mucosa in presence and absence of chitosan and to study the brain bioavailability of therapeutic agents.